In 2006, Fountain, a customer service representative with a decade of service, discovered the IRS didn't have the time or resources to verify telephone tax credit requests from filers claiming to be owed less than $1,500, prosecutors said.
She also later learned that the agency wasn't requiring proof from filers seeking a first-time homebuyer credit worth as much as $8,000.
"The defendants knew it - they knew the money was coming in easy," Special Assistant U.S. Attorney Tiwana L. Wright told jurors during closing arguments Tuesday.
Fountain then turned to her boyfriend, her hairdresser, Natasha Witherspoon, and a friend, Howard Chilsom, to recruit participants as straw filers, prosecutors said. They enlisted drug addicts, welfare recipients and ex-cons - people who needed cash and were willing to hand over a chunk of their refunds, from $400 to $3,000.
When she didn't get her cut quickly enough, Fountain filed another form rescinding the tax credit request, and the straw filers got letters from the IRS demanding the money back, prosecutors said.
Testifying in her own defense, Fountain denied any wrongdoing.
Her lawyer didn't dispute fraudulent returns were filed and improper refunds cashed, but suggested she was framed, possibly even by Ishmael, her codefendant and father to her children.
The lawyer, Michael Engle, said others used Fountain's name and position inside the IRS to "add an air of credibility" to their scheme and persuaded people to lend their names and personal data.
"The word was all over the neighborhood," Engle told jurors. "It was everywhere - and Ms. Fountain was the perfect front."
Wright, who prosecuted the case with Assistant U.S. Attorney Joseph Khan, pointed to forensic evidence that Fountain struggled to rebut.
Investigators from the IRS Criminal Division and the Treasury Department's Inspector General for Tax Administration matched Fountain's fingerprint on a stamp used to mail a fraudulent return - her own.
It was an amended return they said she sent in 2007 to claim a $1,379 telephone tax credit refund, an amount she would have deserved only if she had monthly phone bills of more than $1,000.
They also showed jurors handwriting samples to highlight Fountain's vindictive side - arguing that she forged the signature of another woman on a letter rescinding that woman's refund request. The letter made the woman a target of IRS collections.
Jurors acquitted the defendants of a separate scheme to collect refunds from an education-expense credit.
Still, Fountain faces more than a dozen years in prison under federal sentencing guidelines, Khan said.
Dalzell scheduled her sentencing for June 17.
Contact John P. Martin at 215-925-2649, at firstname.lastname@example.org or @JPMartinInky on Twitter.